Al Duhail described the Brazil international as a “great asset” after confirming his arrival.
The 31-year-old Coutinho was a record signing for Barcelona when joining the Catalan club in a deal worth up to 160 million euros (then $192 million) in 2018.
But his time at the Nou Camp did not go to plan as injury problems saw him fail to live up to expectations and led to loans at Bayern and Villa. He joined Villa in a permanent deal last year, but did not appear to be part of manager Unai Emery’s plans this season after making just two substitute appearances.
He made 43 appearances for Villa and scored six goals.
Coutinho joined Liverpool from Inter in 2013 and the money earned from his move to Barcelona played a big part in Jurgen Klopp’s rebuild that saw the Merseyside club win the Champions League and the Premier League in the following years.
Al Duhail won the Qatar league last season and hopes Coutinho’s arrival will boost its chances of triumphing in the Asian Champions League.
Qatar hosted the men’s World Cup last year, but since then it has been Saudi Arabia that has established itself as a powerhouse of world soccer.
Reporting by The Associated Press.
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